Across
- 1. A non-ohmic conductor that only allows current to flow in one direction
- 4. Radioactive particle that has virtually no mass and an atomic number of -1.
- 6. A type of resistor which has a resistance that depends on light intensity
- 11. Formed when an atom gains or loses electrons
- 12. The exposure of an object to radiation that does not result in the object becoming radioactive. Strawberries passing under a radioactive source to kill bacteria is an example of this.
- 14. A measure of the proportion of energy that is transferred usefully
- 15. The maximum velocity that a falling object will reach which occurs when drag and weight are equal
- 18. The unit of work done
- 19. A quantity that has magnitude only
- 20. A highly penetrating radioactive source that can pass through aluminium but is stopped by a thick lead block
Down
- 2. Two forces which combine to give zero are said to be in ______________
- 3. The change of state of a substance from a solid to a gas missing out the liquid phase
- 4. The unit of radioactivity
- 5. The product of mass and velocity
- 7. The ratio of mass to volume
- 8. The slitting of atomic nuclei by an chain reaction
- 9. The sum of the potential and kinetic energy of a particle (two words)
- 10. A measure of the stiffness of a spring measured in N/m (two words).
- 13. The blue wire in a plug
- 16. The name given to two atoms that have the same atomic number but a different mass number
- 17. A group of objects that interact together